I don't know what is going on but let me post a few questions for you to consider:

1. What operating system?
2. What Oracle version?
3. Have you verified your operating system (vendor and version) are supported with your Oracle version?
4. Did you validate that you followed Oracle's Linux installation docs exactly and that every kernel parameter and RPM is installed correctly and/or valid?

If you had done any sort of research you would find that using ASMLib is not necessary and more often than not causing unwanted and un-necessary grief in your environment. IMProfO, it is a complete waste of time trying to install and configure it. Configure your device permissions with udev or multipathd and just move on.

I used asmlib one time a few years ago... it was so frustrating I removed it an reinstalled the cluster without it. I have installed more than 100 cluster nodes in clusters of various sizes, so I kind-of know what I am talking about.

Since it only exists (I use that term {exists} very loosely) on the linux, proves that you really do not need it.

Oracle sells it.
Oracle documents it.
Oracle supports it.
Tens of thousands of people have installed it without issue.
I doubt you will ever see a "best practices" paper explaining the advantages of not having it available. I know, for sure, I wouldn't write one.

It looks like you are not using the UEK kernel. It is my understanding it is not supported on the Red Hat kernel starting with 6.0.

Oracle's announcement that ASMlib is included in the kernel specifically calls for UEK. According to Oracle's web site, "The Oracle ASMLib kernel driver is now included in the Unbreakable Enterprise Kernel. No driver package needs to be installed when using this kernel. The oracleasm-support and oracleasmlib packages still need to be installed from ULN."
http://www.oracle.com/technetwork/topics/linux/asmlib/index-101839.html

Like I said, 100+ nodes, 70+ clusters (dev/test/production) on Linux, HPUX, AIX, Solaris. If the OS is installed correctly, (udev/multipathd/powerpath etc.) and everything else is configured properly, it is a piece of cake. Once ASM "tags" the device as a part of a diskgroup, I have never had issues even when multipathd "renames" a /dev/mapper device. I always partition off the first 1Mb of the device using a single partition starting at cylinder 2. After that, no problems.

902835 wrote:
It looks like you are not using the UEK kernel. It is my understanding it is not supported on the Red Hat kernel starting with 6.0.

Oracle's announcement that ASMlib is included in the kernel specifically calls for UEK. According to Oracle's web site, "The Oracle ASMLib kernel driver is now included in the Unbreakable Enterprise Kernel. No driver package needs to be installed when using this kernel. The oracleasm-support and oracleasmlib packages still need to be installed from ULN."http://www.oracle.com/technetwork/topics/linux/asmlib/index-101839.html

damorgan, this makes my point. I would also say that "supported" is also used very loosely - it will only be supported on UEK going forward.

I doesn't make your point at all. The point it makes is that Oracle invests its development efforts into projects where it expects to receive the largest return on investment. Not once have I ever confused Larry Ellison's company with a non-profit charitable foundation.

The point is the one I made in my first post on this thread which perhaps you should re-read. If you want to be successful with Oracle use supported documented configurations. This statement is as appropriate to a discussion of ASM as it is to a discussion of any other installation/configuration topic. Your argument reads to me like: "Oracle doesn't support RAC on VMWare therefore RAC has no value" which is a proposal I totally reject.

ASMlib is not mandatory, but makes managing ASM devices easier to manage and provides a more efficient I/O path. Some of it is negotiable, however, I think your negative experience with the product in the past is NO good reason to advice how obsolete or useless ASMlib was. Because, sorry, it isn't. Please do the research.

The reason why oracle ASMlib is included and supported only by the Oracle UEK kernel is not to force people to use Oracle Linux, but due to Red Hat. Oracle was obviously forced to support Oracle kernel modules only for their own kernel, for very good reasons. Red Hat officially said "Yes, we undercut Oracle with hidden Linux patches".

Dude wrote:
ASMlib is not mandatory, but makes managing ASM devices easier to manage and provides a more efficient I/O path. Some of it is negotiable, however, I think your negative experience with the product in the past is NO good reason to advice how obsolete or useless ASMlib was. Because, sorry, it isn't. Please do the research.

The reason why oracle ASMlib is included and supported only by the Oracle UEK kernel is not to force people to use Oracle Linux, but due to Red Hat. Oracle was obviously forced to support Oracle kernel modules only for their own kernel, for very good reasons. Red Hat officially said "Yes, we undercut Oracle with hidden Linux patches".

So for those of us that do not use UEK, whether or not to use ASMLib is really not an option. If it is not supported, I would hate to "force" install it and have something go wrong on my production servers. So, whether or not I do the "research", the fact it will not be supported on RHEL6 only enforces my opinion does it not?

I suggest to create a new topic with a link to this thread as reference, with a subject "Oracle ASMlib is useless and obsolete".

You may personally prefer RHEL instead of the Oracle UEK kernel, or have any other reason that forces you to use the Red Hat kernel, that is your choice, as is the computer you bought. But you cannot say a product is not supported because you are not able to match the product requirement. Not unless perhaps you are the one to set standards, which sorry, I don't think so.

However, my initial point was that because you made a bad experience with ASMLib, is no reason to tell everyone the product is bad, useless and obsolete. Here is where I think you might want to do the research.

If you post in a Linux forum that Windows is bad might give you some applause, but saying Oracle ASMLib is useless in an Oracle forum is sooner or later asking for trouble, unless everyone agrees ;-)

Thank you Dude ... my point exactly. Onedbguru you are far outside the mainstream with what you've written. I can't think of too many people I respect in this business that would agree with you in any substantive way.

If you choose an unsupported configuration and have problems ... the issue is you not Oracle.
If you choose to not read and follow the published docs ... the issue is you not Oracle.
If you have a problem and stop working it rather than opening an SR with MyOracleSupport ... same conclusion.

ASMlib is very valuable. You should not dismiss the product just because it didn't cater to your personal specification.

Do not use AsmLib. Do not want it. Do not need it. And still looking for real technical reasons why it should be used.

And as it is optional and not mandatory (as per Oracle notes, prerequisites and RAC cookbooks), one has the choice of using it. Or not.

In my case (on all RAC clusters I've build and admin'ed), not. We use the same driver stack that is used by many of the www.top500.org Linux clusters. On seriously large SANs. Udev and multipath. Default kernel libs for many releases now - and something that AsmLib runs on top of.